I have created an user only with create session role but when I use that account to see what objects it's got access to, I realize this account can whatch the folder users and tables (SYS, MDSYS) even when I only granted it CREATE SESSION, and I dont want this user to see the other DBA users or tables i just want him to select on a view and nothing else.
How can I avoid this user to see this folders by the way I am working on PL/SQL